On May 8,1855, in the days before there were any bridges across the wide Missouri, a surveyor named Charles Manners and two teams of eight surveyors under contract to the US government crossed the already fabled and still untamed river in a canoe piloted by a local Native American tribal member. It took them several trips back and forth across the river to move the entire team and all their gear. On the last trip the canoe almost swamped and sank because it was overloaded down to the gunnels with a cast iron monument that weighed between five hundred and six hundred pounds. The surveyors noted in their records that only the considerable paddling skills of their Indian canoeist kept them from sinking.
Once the survey team and their gear were safely on the west side of the Missouri, they hauled the iron marker to a high bluff overlooking the river valley. After some searching they found a wooden post overgrown with weeds that had been erected the previous year to mark the place where the fortieth parallel of latitude intersects the Missouri.